Elephants are highly social and intelligent mammals that rely on a complex, multifaceted communication system to navigate their world and maintain group cohesion. Their methods of exchanging information are incredibly diverse, utilizing a wide range of vocalizations, touch, sight, smell, and even ground vibrations. This multimodal approach allows elephant families, which can be scattered across vast distances, to coordinate their movements, share emotional states, and signal intentions to one another in their constantly changing environment. Their communication is a sophisticated blend of audible sounds, inaudible long-distance calls, and physical signals.
The Elephant’s Vocal Repertoire
The most recognizable sounds made by elephants are those that fall within the range of human hearing, forming a repertoire used primarily for short-to-medium distance interactions. The iconic trumpet is produced by pushing air through the trunk and is generally a high-energy sound associated with states of high arousal. Trumpets can signal excitement, such as during play or greeting, or act as a warning of distress or aggression.
The elephant’s larynx, the largest among all mammals, also produces a variety of audible sounds, including roars, bellows, and snorts. Roars and bellows are often used in aggressive displays or when elephants are highly agitated, serving as loud, high-energy warnings. Snorts signal changes in activity or mild arousal and become louder during more intense situations.
The audible portion of the elephant’s vocal range also includes rumbles, which are deep, resonant sounds used for close-range social exchanges. These rumbles are primarily used for greeting, expressing contentment, or maintaining social bonds among closely situated individuals within the herd.
The Hidden World of Infrasound
A unique and scientifically fascinating aspect of elephant communication is their use of infrasound, which consists of sounds that are below 20 hertz (Hz) and are therefore inaudible to the human ear. These extremely low-frequency vocalizations are produced within the elephant’s massive larynx. Research confirms that infrasound is produced by the self-sustained vibration of the long vocal folds, similar to how humans produce speech.
The physical properties of these low-frequency sound waves allow them to travel much farther than higher-pitched sounds, often reaching up to several miles through the air without significant degradation. This long-distance acoustic channel is employed to coordinate the movements of widely dispersed herds, which is essential for survival in their vast habitats. The sounds are also utilized for broadcasting specific messages, such as the “let’s go” rumble used by the matriarch to signal the herd to move.
Infrasound plays a prominent role in reproductive communication, with females using specific low-frequency calls to signal their readiness to mate. African elephant calls in the infrasonic range are recorded to be as high as 117 decibels, allowing for communication over a maximum range of around 10 kilometers. The ability to communicate over such large territories provides a private channel for elephants to maintain their complex social lives and warn others about distant threats.
Communication Beyond Vocalization
Beyond the auditory spectrum, elephants rely on a sophisticated array of non-vocal methods, including the remarkable ability to communicate through ground vibrations. This seismic communication occurs when low-frequency rumbles, or even physical movements like mock charges, are transmitted through the ground as vibrations or Rayleigh waves. These ground-borne signals can travel even further than airborne sound waves, with waveforms created by locomotion traveling up to 32 kilometers.
Seismic Detection
Elephants are uniquely adapted to detect these seismic signals through their feet and head, a process sometimes called “listening” with their feet. Specialized cushion pads on their feet contain cartilaginous nodes and mechanoreceptors, which are sensitive to vibrations and help transmit the signals. When detecting seismic signals, an elephant may exhibit “freezing behavior,” leaning forward to put more weight on its front feet to better receive the vibrations.
Tactile and Visual Cues
Close-range communication is heavily reliant on tactile and visual cues, which reinforce social bonds and convey immediate intentions. Tactile communication involves physical contact, such as the intertwining of trunks during greeting or reassurance, and a mother touching her calf with her trunk or foot to guide it. Visual displays are used to signal intent. Spreading the ears wide or raising the head is used to appear more threatening in aggressive situations, while lowering the head and flattening the ears signals submissiveness.
Chemical Communication
Chemical communication adds another layer of complexity, primarily through the use of semiochemicals, which are detected by the elephant’s highly developed sense of smell. These chemical signals are secreted through urine, feces, and the temporal gland, a structure located on the side of the head. Males in a state of musth, a period of heightened testosterone, release pungent odors from their temporal glands that signal their reproductive status and are of interest to females.